The youngest children lag behind older classmates by the age of seven and struggle to properly catch up throughout compulsory education, it was revealed.

Despite being given additional help by parents, those born in August are 20 per cent more likely to take vocational qualifications at college and a fifth less likely to attend an elite Russell Group university than those with September birthdays.

The study – published by the Institute for Fiscal Studies – also lays bare the extent to which a child’s date of birth influences their self-perception, social and emotional development and chances of being bullied at school.

It comes amid a continuing debate over the best way to educate summer-born children.

The Government insist parents should be given greater control over when children are enrolled in primary education – starting them part-time or later in the reception year to make sure they are “school ready”.

In today’s report, the IFS said further research was needed into the area but suggested children may also need to sit tests at different ages or have their scores “age-adjusted” to address the imbalance.

Ellen Greaves, IFS research economist and the report’s author, said: "It is clear that the consequences of the month in which you were born extend beyond educational attainment.

“We find evidence that, particularly at younger ages, summer-born children are more likely to report being unhappy at school and to have experienced bullying than autumn-born children.

“In light of this, the Government should be concerned about the wider educational experience of summer-born children, who appear to be at a disadvantage in terms of their well-being as well as their test scores."

The report – funded by the Nuffield Foundation – was based on an analysis of three major studies that track children from birth through their education and into early adulthood.

It compared children born in September – at the start of the academic year – to those with birthdays in August to gauge the effect that this had on a range of issues relating to education and personal wellbeing.

Relative to peers with September birthdays, the study found that children born in August were:

• Likely to achieve “substantially” lower scores in national achievement tests and other measures of cognitive skills;

• 20 per cent more likely to study for vocational qualifications if they stay on beyond the age of 16;

• 20 per cent less likely to attend a Russell Group university aged 19;

• Between two-and-a-half and three-and-a-half times more likely to be regarded as below average by their teachers in reading, writing and maths at age seven;

• More likely to exhibit lower social and emotional development;

• Two-and-a-half times more likely to report being unhappy at school and twice as likely to report being bullied at the age of seven,

The study said gaps in performance decreased as children grow up.

It also found that August-born children were – on average – given a “richer home learning environment” than other pupils as parents seek to compensate for disadvantages their children face at school.

The IFS said further research would be published next year about how to address the imbalance at school level.

It suggested this may have “implications for the admissions policies that local authorities choose to follow” or may result in the need to test children at different stages or “age-adjust their scores in some way”.